Generally, within the field of manufacture and assembly of circuit boards, electronic components are fed to a component mounting machine for mechanically and/or electrically mounting the components onto a circuit board. These surface mounted components are often delivered spaced apart along the length of a component tape. Generally, two different types of component tapes are used. The first type consists of a lower carrier tape, preferably plastic, provided with component holding compartments, which are enclosed by a separable, thin, plastic upper cover, or cover tape or protective tape. The second type consists of a cardboard body provided with through holes. The body is provided with separable, thin, plastic, top and bottom cover tapes, thus forming component compartments with the through holes. For ease of description, the term cover tape will hereinafter refer only to the top cover, since the bottom cover is generally not removed during the component mounting process. Consequently, the term carrier tape will hereinafter also refer to the cardboard body with the bottom cover tape provided thereon.
The component tapes are further provided with a lateral portion, extending next to the compartments along the entire length of the component tape, provided with through holes. These through holes are used for engagement with an element of a feeding device of suitable type, the feeding device feeding the component tape into position for picking of components from the tape.
After having positioned the electronic components in their corresponding compartments, the cover tape is attached to the carrier tape, and the component tape is wound on a component tape holder, which within the art generally consists of a component tape reel. Then, the component holder is transferred to a component mounting machine, which feeds a component to a certain predetermined picking position where it can be picked, or collected, by a pick-up head.
The attachment of the cover tape to the carrier tape can, for instance, be performed by providing areas on either or both of the cover tape and the carrier tape with adhesive, or areas where the cover tape is fused to the carrier tape. Generally, these areas are elongated and run along the entire extension of the component tape, along and adjacent to each side of the component compartments.
According to one method for exposing and picking a component from a component tape, a particular type of tape guide is used for bringing the component tape in position for feeding the component tape by interaction with a feeding device, and for picking of components from the tape. The tape guide is provided with an exposure device, the exposure device exposing the components at a picking position, by separating and lifting a portion of the cover tape from the carrier tape, and leaving the remaining portion of the cover at least partially attached to the carrier tape. Furthermore, the tape guide is releasably mountable in a component mounting machine, or in a component magazine for use in the mounting process by the component mounting machine, and virtually operates as an adapter between the component tape and feeding and picking devices of the component mounting machine. Thus, a component tape is preferably first loaded into the tape guide, and the loaded tape guide is then mounted in position in or at the component mounting machine. A more detailed description of the tape guide and the methods of using such a tape guide are disclosed in co-pending U.S. patent applications Ser. Nos. 09/886,482 and 09/886,384, which are incorporated herein by reference.
The use of such a tape guide is advantageous in that, inter alia, it is easy to load the tape guide with a component tape, it is easy to mount the loaded tape guide in a component mounting machine, or in a magazine for use with the component mounting machine, and remove it therefrom, and the tape guide has a simple configuration and build-up without moving parts that is easy and cost-efficient to manufacture.
However, the result from using the above-mentioned method is not altogether satisfactory.